Reproducer.



PATBNTED MAR. 10, 1908." G. L. GHISHOLM.

REPRODUGBR APPLICATION FILED APR. 22. 1907.

A Cizaziesl). ems/20m. l l [EV/55.57.15

A TTOANE VS ducer, of which UNITED STATES! arENT OFFICE.

CHARLES LOGAN OHISHOLM, OFMARYSVILLE, NEW' BRUNSWICK, CANADA.

REPRODUCER. I

Application 'filed Apri1'22,

To all whom 'it may concern:

Be it known that I, CHARLES-LOGAN'CHIS HOLM, a subject'of the Kill of England, re-"' ject in view is to provide a constructionan'd arrangement of diaphragm-and stylus where without departin -the ai i bythe sound\Waves or beats affect the diahragm on truly concentric 'lmes .starting from the precise center of the diaphragm and the stylus receives an accurate vibration in accordance with the impressions on the record, and conveys them with the least resistance and a minimum number of parts directly to the diaphragm at its center to avoid false or secondary vibrations in the diaphragm due to untrue vibrations of the conveying means, the diaphragm being su'p ported only at its pleriph'ery, being W-holy unobstructed on bot surfaces, and there being no attachment to the diaphragm of the means by Which/the vibrations of the'stylus are conveyed thereto. 1 g

Further objects and advantages oft-he in-' vention will ap ear in the following description, andit will be understood'that various chan es in the form, proportions, and minor details of construction may be resorted to from thespirit or sacri-- ficing any 0 vantages of theinventionf In the drawing :Figure 1 is aside view of a reproducer constructed in accordance with the invention. Fig. 2 is a sectional view'of the same. Fi 3 is a detail view in perspective of the sty us arm applied in the opera-f tive position to the supporting plate. Fig.- 4 is a detail sectional view of the contact end of the stylus arm showing the preferred embodiment of the invention. Similar numerals of reference are employed to indicate corresponding arts throughout the several 'figures of the (rawm s. In the construction illustrated, the invention is shown applied to a reproducer of the Edison I type, consisting of a sound. box formed of a tubeplate 10 having a flange 11', and an interior shoulder or seat 12 upon which the diaphra m 13 is arran ed, and-in contact With which it is iirmly lield at its Specification of Letters Patent.

periphery by the ring nut- 14. The tube 15 Patented March 10, 1908.

1907. Serial N0. 369,607.

which extends from the tube plate and communicates interiorly with th sound box is of the ordinary outwardly enlarged bore and isfdesigned to be used'in connection with a horn of any preferred construction. The.

sound box is hing'edly connected at. 16 with the counterbalance 17 and is adapted to be secured in any 1 preferred or the usual manner to the frame 0 the machine, not illustrated. The diaphragm within its supported periphery is whollyunobstructed as to both surfaces, and the 1m ressions of the record are, conveyed thereto y means of a stylus lever 17 which is pivotallyfmounted at 18 upon a bracket depending from the supporting plate and isprovided with an arm-19 which terminates in a stylus or contact point 20,

and While the arm is illustrated and is preferably constructed of very small diameter, -1t w ll be "noted. that from-a pointnear the pivot to. the contact point it is arranged almost entirely' on "a .llne perpendicular to that portionof the stylus lever which is between the pivot'andthe stylus point, and 'fWhrohmaybe: termedthe body portion of the structure, so :that the leverwhile being light and-sensitive is not strained in use on atransverse line, but on a substantially longitudinal line to avoid any tendency of flex-.

mg. Beneath the body portion of the stylus lever, and preferably close to the stylus point,; is arranged a yielding cushion 21, which may be of "soft ,rubber or any other resilientor spr ng material, or even a spring,

adapted to yield under a very slight pressure and yet respond promptly to'hold'thestylus point in'the desired contact and with the re uisite stress against the record.

y this means the impressions of the record are conveyed directly to the contact point which is in contact with the diaphragm v by. a'single meinbenj so that there is no loss of vibration due to either lost motion or yielding or springing of the member itself, and inorder to prevent any possible screeching.b'(-)twcen the contact point of the stylus lever and the diaphragm the said point of contact is provided. with an' interposed layer of some clastic'or semi-elastic substance, indicated at 22. This cushion should be so thin as to have no appreciable damping efvibrations which constitute the disadvantages of reproducers in which the connection between the stylus lever or arm and the diaphragm includes "a member attached to and sometimes through the diaphragm, so that the diaphragm is not only impelled in one direction by a push applied to the stylus connections, but is also pulled so that the vibrations interferewith each other.

I claim 1. A reproducer having a peripherally supported but otherwise superficially unobstructed diaphragm, and a stylus carrier unconnected with the diaphragm but having a contact point provided with a film-like cushion in contact but not connected with the surface of the diaphragm at the center.

2. A reproducer having a peripherally supported but otherwise superficially unchstructed diaphragm, and a yieldingly-supported stylus carrier provided with a contact point provided'with a film like cushion which is in contact but not connected with the surface of the diaphragm at its center.

,structed diaphragm, and a pivotal stylus carrier having a substantially non-dam Jing, cushioned contact point for contact with the diaphragm at its center.

5. .A reproducer having a peripherally supported but otherwise superficially unoh structed diaphragm, and a pivotally mounted stylus carrier terminating at one end in a stylus point and at the other end in a contact point, a cushion of film-like thinness on the contact )oint of the stylus carrier, and a cushioning device arranged in operative rclation. with the stylus end. of the stylus carrier to yieldingly impel the same toward the record.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signature in the presence of two witnesses.

CHARLES LOGAN CHISHOLM.

Witnesses:

E. B. EDWARDS, LOUIS MADDRE. 

